Electromagnetic switch



J. EATON.

ELECTROMAGNETIC SWITCH. APPLICATION FILED ocT. I, 1918.

1 3 34, 1 44 Patented Mar. 16, 1920.

Fig; I

Inventor:

John E at. on

, His Attorney UNTTED sTATEs PATENT oEEroE- JOHN EATON, 0F SCHENECTADY, NEW YORK, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTROMAGNETIC SWITCH.

Application filed October 7,

To atl whom t may concern.'

Be it known that I, JOHN' EATON, a s'ubject of the King of Great Britaimresiding at Schenectady, county of Schenectady, State of New York, have linvented certain new and useful Improvements in Electromagnetic Switches, of which the following is a specification.

My invention relates to improvements in electromagnetic switches intended principally for use on alternating current circuits although not necessarily limited to this application. l

As is Well known, the armature or core of an electromagnetic switch tends to' chatter` against the stationary member when used on an alternating current circuit due to the alternations. This chattering is decidedly objectionable and various means have been provided for overcoming the difficulty. It has been found thatif the moving part engages the stationary part so that it bea-rs uniformly over the surface the chattering will be greatly reduced, if not entirely done away with. I'Vhere the parts are rigidly mounted, however, such a contact can only be obtained by very accurate work which involves expert hand workmanship the cost of which is very excessive. It has been found that substantially the same result may be obtained, however, by leaving the parts free to aline and adjust themselves to each other, and it is the object of -my invention to provide a simple and effective arrangement whereby such alinement may be obtained. My invention will be understood from the following description taken in connection with the accompanying drawing in which I have shown my invention embodied in concrete form for purposes of illustration.

In the drawing Figure 1 is a side elevation of a magnetic switch embodying myrinvention; Fig. 2 is a side view of the arma-d ture and Fig. 3 is a sec-tional' view of the armature mounted on the switch arm, taken' on the line 3-3 of Fig. 2.

Referring to the drawings, 1 represents the insulating base upon which the switch part-s are mounted. These switch parts consist of an electromagnet composed of alwinding 2 mounted upon one leg of the U-shaped'laminated core 3, provided with an air gap 4, and a switch arm 5, pivoted atv 6. The arm 5 operates a contact member 7 which cooperates with a stationary contact Specification of Letters Patent. Patented 31311'. 16, 1920.

191e. serial No. 251,098.

In accordance with my invention the 1 armature, which is laminated, is mounted on a pin 15 which is secured at its ends in the switch arm 5, t-he hole for the pin being the size of the pin for a very short distance at 16, and being enlarged at 17 and 18 so as to provide considerable clearance. The bearing at 16 is very short so that the armature may rock on the pin aty the bearing in all directions. This pin is preferably at the upper end of the armature. At the other end I preferably provide a pin 14: extending into a larger opening in thev armature. The liole for the pin 14 provides clearance all the way around so that normally the pin does not have a bearing in the armature. This pin, therefore, merely acts to limit the movement of the armature with reference to the arm 5.

By this arrangement it will be seen that when the winding 2 is energized the armaturefwill be drawn up against the pole faces 12 and 13 and the armature, being loosely `mounted, vis free to aline itself so as to make a uniform engagement with the two pole faces. 'The arrangement is exceedingly simple and involves no accurate fitting or surfacing.

While I har-fe described my invention as embodied in concrete form in accordance with the provisions of the patent statutes, it

should be understood that I do not limit my F Ainvention thereto, since various modifications thereof will suggest themselves to those skilled in the art without departing from the spirit of my invention the scope of which is set forth in the annexed claims.

What I- claim as new and desire to secure by Letters YPatent of the United States, is

1. An electromagnetic switch comprising an electromagnet and a pivoted switch arm,

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an armature therefor, andC a bearing pin secured to the switch arm and passing freely through an opening in the armature. said opening being reduced midway thereof to form a short bearing for the armature upon which. the latter may rock.

2. An electromagnetic switch comprising an electromagnet zand apivoted switch arm,-

an armature therefor, a bearing pin secured to the switch arm and passingV freely through one end of the armature but having :L short supporting bearing thereon midway on the armature upon which the latter may rock and a pi'n entering the other end of the l(irnriaiture but'out of Contact therewith when the arma-ture engages the electromagnet.

3. An electromagnetic Switch Comprising an eleetromagnet and a. pivoted `switch arm, an arma-ture therefor, a bearing pin secured to the Switch arm and passing freely through a. similarly shaped opening in the upper end of the armature said opening being reduced midway thereof to form a. short bearing for the armature upon which the latter may rock, and a pin entering the lower end of the armature but out of Contact therewith when the armature lengfrges the electro magnet.

In witness whereof I have hereunto set my hand this 3rd day of Uotober, 1918.

JOHN EATON. 

